MoviePipeline: Disabling Auto Exposure in Project Settings not respected

The high-res tiling method checks for the exposure method specified on the camera, and forces it to Manual exposure if it's not already there. It shouldn't force this if the project settings have already disabled auto-exposure as the scene will be exposed correctly.

1. Disable Auto Exposure in the project settings.
2. Set up a scene without using auto exposure and note that the exposure is correct in the viewport.
3. Create a simple level sequence with a camera that does NOT override Exposure Method or Exposure Compensation
4. Render with MRQ with default settings, see that it is ok
5. Enable the high-res tiling feature (which does not support auto-exposure). Note that the render comes out black or very dark.